http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Nowak-Kró,l, Agnieszka,Fimmel, Benjamin,Son, Minjung,Kim, Dongho,Wü,rthner, Frank The Royal Society of Chemistry 2015 Faraday discussions Vol.185 No.-
<P>Foldamer systems comprised of two perylene bisimide (PBI) dyes attached to the conjugated backbones of 1,2-bis(phenylethynyl)benzene and phenylethynyl-bis(phenylene)indane, respectively, were synthesized and investigated with regard to their solvent-dependent properties. UV/Vis absorption and steady-state fluorescence spectra show that both foldamers exist predominantly in a folded H-aggregated state consisting of π–π-stacked PBIs in THF and in more random conformations with weaker excitonic coupling between the PBIs in chloroform. Time-resolved fluorescence spectroscopy and transient absorption spectroscopy reveal entirely different relaxation pathways for the photoexcited molecules in the given solvents, <I>i.e.</I> photoinduced electron transfer leading to charge separated states for the open conformations (in chloroform) and relaxation into excimer states with red-shifted emission for the stacked conformations (in THF). Supported by redox data from cyclic voltammetry and Rehm–Weller analysis we could relate the processes occurring in these solution-phase model systems to the elementary processes in organic solar cells. Accordingly, only if relaxation pathways such as excimer formation are strictly avoided in molecular semiconductor materials, excitons may diffuse over larger distances to the heterojunction interface and produce photocurrent <I>via</I> the formation of electron/hole pairs by photoinduced electron transfer.</P>
β decays of the heaviest N=Z−1 nuclei and proton instability of In97
Park, J.,Krü,cken, R.,Lubos, D.,Gernhä,user, R.,Lewitowicz, M.,Nishimura, S.,Ahn, D. S.,Baba, H.,Blank, B.,Blazhev, A.,Boutachkov, P.,Browne, F.,Č,eliković,, I.,de France, G.,Doornen American Physical Society 2018 Physical review. C Vol.97 No.5
Woo, Seonghoon,Litzius, Kai,Krü,ger, Benjamin,Im, Mi-Young,Caretta, Lucas,Richter, Kornel,Mann, Maxwell,Krone, Andrea,Reeve, Robert M.,Weigand, Markus,Agrawal, Parnika,Lemesh, Ivan,Mawass, Mohamad Nature Publishing Group 2016 Nature Materials Vol.15 No.5
<P>Magnetic skyrmions(1,2) are topologically protected spin textures that exhibit fascinating physical behaviours(1-6) and large potential in highly energy-efficient spintronic device applications(7-13). The main obstacles so far are that skyrmions have been observed in only a few exotic materials and at low temperatures(1-4,6-8), and fast current-driven motion of individual skyrmions has not yet been achieved. Here, we report the observation of stable magnetic skyrmions at room temperature in ultrathin transition metal ferromagnets with magnetic transmission soft X-ray microscopy. We demonstrate the ability to generate stable skyrmion lattices and drive trains of individual skyrmions by short current pulses along a magnetic racetrack at speeds exceeding 100m s(-1) as required for applications. Our findings provide experimental evidence of recent predictions(10-13) and open the door to room-temperature skyrmion spintronics in robust thin-film heterostructures.</P>
THE LOCAL DUST FOREGROUNDS IN THE MICROWAVE SKY. I. THERMAL EMISSION SPECTRA
Dikarev, Valeri,Preuß, Oliver,Solanki, Sami,Krü,ger, Harald,Krivov, Alexander IOP Publishing 2009 The Astrophysical journal Vol.705 No.1
<P>Analyses of the cosmic microwave background (CMB) radiationmaps made by the Wilkinson Microwave Anisotropy Probe (WMAP) have revealed anomalies not predicted by the standard inflationary cosmology. In particular, the power of the quadrupole moment of the CMB fluctuations is remarkably low, and the quadrupole and octopole moments are aligned mutually and with the geometry of the solar system. It has been suggested in the literature that microwave sky pollution by an unidentified dust cloud in the vicinity of the solar system may be the cause for these anomalies. In this paper, we simulate the thermal emission by clouds of spherical homogeneous particles of several materials. Spectral constraints from the WMAP multi-wavelength data and earlier infrared observations on the hypothetical dust cloud are used to determine the dust cloud's physical characteristics. In order for its emissivity to demonstrate a flat, CMB-like wavelength dependence over the WMAP wavelengths ( 3 through 14 mm), and to be invisible in the infrared light, its particles must be macroscopic. Silicate spheres of several millimeters in size and carbonaceous particles an order of magnitude smaller will suffice. According to our estimates of the abundance of such particles in the zodiacal cloud and trans-Neptunian belt, yielding the optical depths of the order of 10(-7) for each cloud, the solar system dust can well contribute 10 mu K ( within an order of magnitude) in the microwaves. This is not only intriguingly close to the magnitude of the anomalies ( about 30 mu K), but also alarmingly above the presently believed magnitude of systematic biases of the WMAP results ( below 5 mu K) and, to an even greater degree, of the future missions with higher sensitivities, e. g., Planck.</P>
Hough, L. E.,Jung, H. T.,Krü,erke, D.,Heberling, M. S.,Nakata, M.,Jones, C. D.,Chen, D.,Link, D. R.,Zasadzinski, J.,Heppke, G.,Rabe, J. P.,Stocker, W.,Kö,rblova, E.,Walba, D. M.,Glaser, M. A. American Association for the Advancement of Scienc 2009 Science Vol.325 No.5939
<P>In the formation of chiral crystals, the tendency for twist in the orientation of neighboring molecules is incompatible with ordering into a lattice: Twist is expelled from planar layers at the expense of local strain. We report the ordered state of a neat material in which a local chiral structure is expressed as twisted layers, a state made possible by spatial limitation of layering to a periodic array of nanoscale filaments. Although made of achiral molecules, the layers in these filaments are twisted and rigorously homochiral--a broken symmetry. The precise structural definition achieved in filament self-assembly enables collective organization into arrays in which an additional broken symmetry--the appearance of macroscopic coherence of the filament twist--produces a liquid crystal phase of helically precessing layers.</P>
Hagen, Ralf Matthias,Frickmann, Hagen,Ehlers, Julian,Krü,ger, Andreas,Margos, Gabriele,Hizo-Teufel, Cecilia,Fingerle, Volker,Rakotozandrindrainy, Raphael,Kalckreuth, Vera von,Im, Justin,Pak, Gi De Elsevier 2018 Acta tropica Vol.177 No.-
<P><B>Abstract</B></P> <P>The occurrence of tick-borne relapsing fever and leptospirosis in humans in Madagascar remains unclear despite the presence of their potential vectors and reservoir hosts.</P> <P>We screened 255 <I>Amblyomma variegatum</I> ticks and 148 <I>Rhipicephalus microplus</I> ticks from Zebu cattle in Madagascar for <I>Borrelia</I>-specific DNA. <I>Borrelia</I> spp. DNA was detected in 21 <I>Amblyomma variegatum</I> ticks and 2 <I>Rhipicephalus microplus</I> ticks. One <I>Borrelia</I> found in one <I>Rhipicephalus microplus</I> showed close relationship to <I>Borrelia theileri</I> based on genetic distance and phylogenetic analyses on 16S rRNA and <I>flaB</I> sequences. The borreliae from <I>Amblyomma variegatum</I> could not be identified due to very low quantities of present DNA reflected by high cycle threshold values in real-time-PCR. It is uncertain whether these low numbers of <I>Borrelia</I> spp. are sufficient for transmission of infection from ticks to humans.</P> <P>In order to determine whether spirochaete infections are relevant in humans, blood samples of 1009 patients from the highlands of Madagascar with fever of unknown origin were screened for <I>Borrelia</I> spp. − and in addition for <I>Leptospira</I> spp. − by real-time PCR. No target DNA was detected, indicating a limited relevance of these pathogens for humans in the highlands of Madagascar.</P> <P><B>Highlights</B></P> <P> <UL> <LI> <I>Borrelia</I> spp. DNA was detected in <I>Amblyomma (A.) variegatum</I> ticks and <I>Rhipicephalus (R.) microplus</I> ticks in Madagascar. </LI> <LI> DNA of a <I>Borrelia (B.) theileri</I>-related borreliae was detected in <I>R. microplus</I> for the first time in Madagascar. </LI> <LI> Only low amounts of <I>Borrelia</I> spp. DNA were detected in the assessed ticks, indicating low numbers of organisms and indicating an at the most limited risk of transmission to humans. </LI> <LI> <I>Borrelia</I> spp. DNA was absent in the blood of fever patients from the highlands in Madagascar. </LI> <LI> <I>Leptospira</I> (<I>L.</I>) spp. DNA was absent in the blood of fever patients from the highlands in Madagascar. </LI> </UL> </P>
Choi, Sun Young,Calmano, Thomas,Kim, Mi Hye,Yeom, Dong-Il,Krä,nkel, Christian,Huber, Gü,nter,Rotermund, Fabian Optical Society of America 2015 Optics express Vol.23 No.6
<P>We demonstrate a diode-pumped femtosecond-laser-inscribed Yb:YAG channel waveguide laser, Q-switched by using single-walled carbon nanotubes (SWCNTs) near 1029 nm. We used saturable absorber mirrors (SAMs) fabricated by depositing SWCNTs on three different output couplers. Best performance of the 9.3-mm-long ultra-compact Q-switched waveguide laser is obtained with an output coupling transmission of 20%. In this case, a maximum average output power of 60 mW with a corresponding pulse energy of 37.7 nJ and a pulse duration of 88 ns at 1.59-MHz repetition rate were achieved. The highest pulse energy of 39.2 nJ and the shortest pulse duration of 78 ns were obtained with 30% and 10% output couplers, respectively.</P>
Design of Neural Networks Model for Transmission Angle of a Modified Mechanism
Şahin Yildirim,Selçuk Erkaya,Şükrü Su,íbrabim Uzmay 대한기계학회 2005 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.19 No.10
This paper discusses Neural Networks as predictor for analyzing of transmission angle of slider-crank mechanism. There are different types of neural network algorithms obtained by using chain rules. The neural network is a feedforward neural network. On the other hand, the slider-crank mechanism is a modified mechanism by using an additional link between connecting rod and crank pin. Through extensive simulations, these neural network models are shown to be effective for prediction and analyzing of a modified slider-crank mechanism’s transmission angle.